Category Archives: Milling Stone

We love working with Sandstone, it’s very satisfying as we usually get called in when it looks really horrible and grubby and after some work it ends up looking stunning. The floor in this property in the famous Lake District town of Keswick had been covered with carpet for many years, so when we uncovered it as you can see from the pictures, it was clearly in needed of major attention and a great candidate for restoration.

When the floors this bad there’s no point trying to get a decent clean just by using chemicals alone, so we often offer a system we have perfected at Tile Doctor called “Milling”. We discussed the project in detail with the client and agreed a price and a time to complete the work.

Restoring the Appearance of Red Sandstone

Milling involves the application of several coarse grades of hard diamond pads to the stone using water to lubricate the process, the water also helps make the removal of the soil easier and reduces dust. On this occasion we used coarse 50, 100 and 200-grit milling pads applied in sequence with a weighted rotary floor machine, the floor is rinsed with water between each pad and the soil extracted using a wet vacuum.

We worked our way across the floor using this process. Not only does this give the stone the deepest clean it has ever had but it also cuts back the stone a few millimetres and takes off a lot of roughness leaving the finish a lot smoother, this makes the now Milled Stone a lot easier to maintain in the future as it has a much smoother texture and finish.

Loose grout is a common problem on these older floors, so the next step was to rake out any broken and loose grout between the slabs, clean-up and repoint to match the existing. Once that had set, we gave the floor another lighter clean with Tile Doctor Pro-Clean run along the recessed grout lines with a rush to clean them up. I was then satisfied the floor was a clean and it could be, the floor now needed to dry our before we applied the sealer.

Sealing a Red Sandstone Tiled Floor

We returned the following day and checked the floor was dry using the moisture meter, we don’t recommend applying a sealer to a damp floor as the sealer will not cure properly. All was well, so we then applied several coats of Tile Doctor Colour Grow Sealer, this is a fully breathable, impregnating sealer that will protect the stone from staining whilst enhancing the natural red colour in the Sandstone.

Using a breathable sealer on old stone floors like this is highly recommend as these floors rarely have a damp proof membrane installed and so it’s important to give moisture a way of rising through the floor naturally and evaporating rather than being trapped under the floor where it can eventually build up in the walls.

As you can imagine from the after pictures the customer was happy with the overall outcome and relieved that their decision to remove the carpet had worked out.

Professional Restoration of a Red Sandstone Paved Floor in North Cumbria

The pictures below show a Rough Textured Indian Sandstone floor installed in the Kitchen and Hallway at a property in Bernoldswick which is a small town just outside the Yorkshire Dales national park. The client called us out to have a look at their floor which was very dirty. They were undecided as to what to do with it and were even considering ripping it up and putting a more practical floor down. This Sandstone has a rough texture which traps dirt and can shred mops making it very difficult to maintain so it’s not surprising that the client was close to giving up on it.

Initially we were asked just to deep clean and seal the Stone, but I realised that wouldn’t resolve the problem completely, so I offered a service we call Milling. This is a process involves applying coarse diamond pads with special machinery to remove a good chunk of the rough texture (about 80 to 85% ). It would leave the stone with a much smoother finish which is easier to keep clean, easier to seal and a lot easier to maintain in the future.

After a demonstration was done and a price given for either a clean and seal or to Mill first followed by a clean and seal the customer opted for the latter. This would also prove significantly cheaper than ripping up the floor, hiring a skip to take away the stone, then self-levelling the concrete to get it ready for the new floor, not to mention the cost of the new floor covering.

Cleaning and Milling an Indian Sandstone Tiled Kitchen and Hallway Floor

Milling the stone involves the use of a set of thee milling pads of different grades (50, 100 and 200 grit) which are applied in sequence. You start with the coarse and abrasive 50 grit milling pad and follow this by smoothing this surface with the finer 100 and 200 diamond grit milling pads. Water is used to lubricate and capture the dust which is created during the process resulting in a slurry which needs to be rinsed away and extracted with a wet vacuum between each pad. The process requires the use of a solid weighted rotary machine and a fair bit of muscle power to guide it.

As you can see from the pictures the difference is immense but what you can’t tell from these photos is how smooth the stone feels to the touch as its the rough texture of Sandstone that catches all the dirt and makes it hard to clean, even after it has been cleaned and sealed professionally.

To refine the surface of the Sandstone even further the Milling process is followed by the application of finer grade Burnishing pads, again applied with water and the soil rinsed off between each pad. This process uses no chemical cleaning products only water, Diamond pads and machinery.

Sealing an Indian Sandstone Tiled Kitchen and Hallway Floor

After allowing the stone to fully dry out overnight we finished the job with several coats of Tile Doctor Colour Grow which is a colour enhancing impregnating sealer that protects the stone from within. It gave the stone a nice low-key matt colour enhanced finish that really showed off the character in the stone.

The client was over the moon with the result and were so pleased they had not ripped up the floor!